The Windows Sockets 2 QOS structure is defined in WINSOCK2.H and is reproduced here.
typedef struct _QualityOfService {
FLOWSPEC SendingFlowspec; /* The flowspec for data */
/* sending */
FLOWSPEC ReceivingFlowspec; /* The flowspec for data */
/* receiving */
WSABUF ProviderSpecific; /* Additional provider- */
/* specific parameters */
} QOS, FAR * LPQOS;